This application is based upon Japanese Patent Application Nos. Hei. 10-352948 filed on Dec. 11, 1998, Hei. 10-352949 filed on Dec. 11, 1998, Hei. 11-309621 filed on Oct. 29, 1999, and Hei. 11-309622 filed on Oct. 29, 1999, the contents of which are incorporated herein by reference.
1. Field of the Invention
This invention relates to hydraulic control apparatuses, and particularly to a hydraulic control apparatus in which a motor driving large current circuit unit is integrally assembled with a hydraulic unit.
2. Related Art
Conventionally, a hydraulic unit for adjusting wheel cylinder pressure for performing an anti-skid control. (ABS control or antilock braking system control) or the like, an ECU (electronic control unit) for controlling the hydraulic unit, and a motor driving circuit for actuating a motor such as a pump motor for adjusting brake fluid pressure, are mounted on a vehicle.
Recently, some kinds of apparatuses are designed as module-type to simplify manufacturing steps or to make the apparatus more compact. It is thought to design a module apparatus, in which the hydraulic unit for the ABS control and the ECU are integrally assembled.
For example, it is thought that a housing (a circuit unit housing) made of resin, which accommodates the motor driving circuit unit such as the motor driving circuit and an electronic substrate for controlling a motor actuation, is assembled to an aluminum alloy housing accommodating the hydraulic unit. (First example)
In this case, as shown in FIG. 7, a not-shown solenoid is inserted to a lower portion of a case portion P4 of the circuit unit housing P3; an electronic substrate P2 is assembled to an upper portion of the case portion P4; and then an opening portion of the upper portion of the case portion P4 is covered with a cover P5 so as to seal the circuit unit housing P3. Next, the circuit unit housing P3 is arranged on a hydraulic unit housing P1, and the circuit unit housing P3 is fixed to the hydraulic unit housing by screws P6.
However, when such the hydraulic control apparatus integrated with motor circuit unit is assembled by the above-described steps, the following inconvenience may occur.
That is, it needs to provide a waterproof to the circuit unit housing P3 so that water may not touch the electronic substrate P2 accommodated in the circuit unit housing P3.
For example, when the cover P5 is assembled to the case portion P4, silicon is filled up at an assembling portion so that the case portion P4 is connected with the cover P5 and that silicon performs the waterproof of gaps between the case portion P4 and the cover P5.
Furthermore, a not-shown waterproof packing is provided at a bottom surface of an outer wall P7 of the lower portion of the case portion P4 so as to waterproof between the case portion P4 and the hydraulic unit housing P1. Furthermore, one part of a partition wall P8 of the case portion P4 where a terminal from the solenoid penetrates is waterproofed by filling up silicon, so as to waterproof a lower portion and an upper portion of the partition wall 8 of the case portion P4.
However, such the waterproof steps for protecting the electronic substrate P2 from liquid such as water may lower productivity.
Furthermore, it is thought that a housing (an ECU housing) made of resin, which accommodates solenoid for actuating a electromagnetic valve, an electronic substrate or the like, is assembled to an aluminum alloy housing accommodating the hydraulic unit such as a hydraulic circuit. (Second example)
However, in the case of the second example, the electronic substrate is arranged above the solenoid, and then the electronic substrate is assembled and electrically connected with the solenoid in the ECU housing. Therefore, the electronic substrate needs to be connected after the solenoid is assembled to the hydraulic unit housing. Hence, there would be lack of flexibility for manufacturing steps, and as a result, it may reduce productivity because it is difficult to rearrange or divide the manufacturing steps.
Furthermore, in the case of the second example, when the ECU includes a large current circuit, the following inconvenience may occur. That is, 1) noise due to the large current may cause harmful influence to the other signals; 2) it needs to have a harness for the large current to supply power from the ECU to the solenoid; 3) size of the ECU becomes large; and as a result, 4) throughput of the substrate may be decreased. Therefore, it is preferable to form the hydraulic unit and the motor driving large current circuit in one module, and to separately form the ECU from to the hydraulic unit and the motor driving large current circuit. However, total volume of the module and ECU may increase.
Furthermore, water entering into a motor driving circuit housing or being generated as a result of condensation causes breakdown, rust or erosion. Therefore, it needs to remove such water immediately. However, in the case of the water, since water may adhere on a drain path due to surface tension, it needs to enlarge a size of the drain path and a size of the housing may increase.
This invention has been conceived in view of the background thus far described and its first object is to provide a hydraulic control apparatus, in which waterproof can be efficiently performed.
Its second object is to provide a hydraulic control apparatus, in which waterproof for preventing liquid such as water from touching an electronic substrate or the like accommodated in a housing of a motor driving circuit unit can be efficiently performed.
Its third object is to provide a hydraulic control apparatus, of which manufacturing steps has flexibility enough to assemble an electronic substrate at early stage.
Its fourth object is to provide downsized hydraulic control apparatus, in which a hydraulic unit is integrated with and a motor driving large current circuit.
According to one aspect of the present invention, since an electronic substrate portion, which accommodates an electronic substrate for controlling a pressure generating actuator for generating the brake fluid pressure, is separated from the operation portion, the waterproof of the electronic substrate portion can be easily performed.
According to another aspect of the present invention, an electronic substrate portion is arranged so as to transversally offset with respect to the operation portion. Therefore, the operation portion and the electronic substrate portion are manufactured separately. Thus, since the flexibility of the manufacture increases, the electronic substrate can be assembled at early stage.
According to another aspect of the present invention, a hydraulic unit has a hydraulic unit housing for accommodating a hydraulic mechanism including valves, and the hydraulic unit housing of the hydraulic unit housing includes a valve arrange portion at which the valves are concentrated. Here, a terminal line is connected to the pressure generating actuator by being penetrated through the hydraulic unit housing, and has a shape to detour around the valve arrange portion of the hydraulic unit housing. Therefore, it can reduce an interval between each valve and therefore downsize the total volume because this structure can efficiently use spaces compared to the case where the valves are dispersively arranged.
According to another aspect of the present invention, a hydraulic unit has a channel groove at a portion where the circuit unit housing is confronted with in the hydraulic unit, the channel groove is partly opened to the operation portion and is directly or indirectly communicated with a ventilating opening positioned at a bottom surface of the hydraulic control apparatus.
In this case, almost all the path for draining liquid from the operation portion can be defined as the channel groove. Therefore, the circuit unit housing may have a part of the path or may no path therein. Hence, it can prevent the circuit unit housing from becoming large scale.